<template>
	<div class="login">
		<div id="bgd"><canvas id="myCanvas" :width="width" :height="height"></canvas></div>
		<div id="loginBox">
			<el-form ref="loginForm" :model="loginForm" :rules="loginRules" class="login-form">
				<h3 class="title">药品仓库管理系统</h3>
				<el-form-item prop="username">
					<el-input v-model="loginForm.username" type="text" auto-complete="off" placeholder="账号">
						<svg-icon slot="prefix" icon-class="user" class="el-input__icon input-icon" />
					</el-input>
				</el-form-item>
				<el-form-item prop="password">
					<el-input v-model="loginForm.password" type="password" auto-complete="off" placeholder="密码" @keyup.enter.native="handleLogin">
						<svg-icon slot="prefix" icon-class="password" class="el-input__icon input-icon" />
					</el-input>
				</el-form-item>
				<el-form-item prop="code" v-if="captchaEnabled">
					<el-input v-model="loginForm.code" auto-complete="off" placeholder="验证码" style="width: 63%" @keyup.enter.native="handleLogin">
						<svg-icon slot="prefix" icon-class="validCode" class="el-input__icon input-icon" />
					</el-input>
					<div class="login-code"><img :src="codeUrl" @click="getCode" class="login-code-img" /></div>
				</el-form-item>
				<el-checkbox v-model="loginForm.rememberMe" style="margin:0px 0px 25px 0px;">记住密码</el-checkbox>
				<el-form-item style="width:100%;">
					<el-button :loading="loading" size="medium" type="primary" style="width:100%;background-color: transparent;color: #39f;" @click.native.prevent="handleLogin">
						<span v-if="!loading">登 录</span>
						<span v-else>登 录 中...</span>
					</el-button>
					<!-- v-if="register" -->
					<div style="float: right;"><router-link class="link-type" :to="'/register'">立即注册</router-link></div>
				</el-form-item>
			</el-form>
			<!--  底部  -->
			<div class="el-login-footer"><span>Copyright © 2022-2023 努力地派大星 All Rights Reserved.</span></div>
		</div>
	</div>
</template>

<script>
import { getCodeImg } from '@/api/login';
import Cookies from 'js-cookie';
import { encrypt, decrypt } from '@/utils/jsencrypt';

export default {
	name: 'Login',
	data() {
		return {
			canvas: null,
			context: null,
			stars: [], //星星数组
			shadowColorList: ['#39f', '#ec5707', '#b031d4', '#22e6c7', '#92d819', '#14d7f1', '#e23c66'], //阴影颜色列表
			directionList: ['leftTop', 'leftBottom', 'rightTop', 'rightBottom'], //星星运行方向
			speed: 50, //星星运行速度
			last_star_created_time: new Date(), //上次重绘星星时间
			Ball: class Ball {
				constructor(radius) {
					this.x = 0;
					this.y = 0;
					this.radius = radius;
					this.color = '';
					this.shadowColor = '';
					this.direction = '';
				}

				draw(context) {
					context.save();
					context.translate(this.x, this.y);
					context.lineWidth = this.lineWidth;
					var my_gradient = context.createLinearGradient(0, 0, 0, 8);
					my_gradient.addColorStop(0, this.color);
					my_gradient.addColorStop(1, this.shadowColor);
					context.fillStyle = my_gradient;
					context.beginPath();
					context.arc(0, 0, this.radius, 0, Math.PI * 2, true);
					context.closePath();

					context.shadowColor = this.shadowColor;
					context.shadowOffsetX = 0;
					context.shadowOffsetY = 0;
					context.shadowBlur = 10;

					context.fill();
					context.restore();
				}
			}, //工厂模式定义Ball类
			width: window.innerWidth,
			height: window.innerHeight,

			codeUrl: '',
			loginForm: {
				username: 'admin',
				password: 'admin123',
				rememberMe: false,
				code: '',
				uuid: ''
			},
			loginRules: {
				username: [{ required: true, trigger: 'blur', message: '请输入您的账号' }],
				password: [{ required: true, trigger: 'blur', message: '请输入您的密码' }],
				code: [{ required: true, trigger: 'change', message: '请输入验证码' }]
			},
			loading: false,
			// 验证码开关
			captchaEnabled: true,
			// 注册开关
			register: false,
			redirect: undefined
		};
	},
	watch: {
		$route: {
			handler: function(route) {
				this.redirect = route.query && route.query.redirect;
			},
			immediate: true
		}
	},
	mounted() {
		this.canvas = document.getElementById('myCanvas');
		this.context = this.canvas.getContext('2d');

		this.createStar(true);
		this.drawFrame();
	},
	created() {
		this.getCode();
		this.getCookie();
	},
	methods: {
		//重复动画
		drawFrame() {
			let animation = requestAnimationFrame(this.drawFrame);
			this.context.clearRect(0, 0, this.canvas.width, this.canvas.height);
			this.createStar(false);
			this.stars.forEach(this.moveStar);
		},
		//展示所有的星星
		createStar(params) {
			let now = new Date();
			if (params) {
				//初始化星星
				for (var i = 0; i < 50; i++) {
					const radius = Math.random() * 3 + 2;
					let star = new this.Ball(radius);
					star.x = Math.random() * this.canvas.width + 1;
					star.y = Math.random() * this.canvas.height + 1;
					star.color = '#ffffff';
					star.shadowColor = this.shadowColorList[Math.floor(Math.random() * this.shadowColorList.length)];
					star.direction = this.directionList[Math.floor(Math.random() * this.directionList.length)];
					this.stars.push(star);
				}
			} else if (!params && now - this.last_star_created_time > 3000) {
				//每隔3秒重绘修改颜色其中30个球阴影颜色
				for (var i = 0; i < 30; i++) {
					this.stars[i].shadowColor = this.shadowColorList[Math.floor(Math.random() * this.shadowColorList.length)];
				}
				this.last_star_created_time = now;
			}
		},
		//移动
		moveStar(star, index) {
			if (star.y - this.canvas.height > 0) {
				//触底
				if (Math.floor(Math.random() * 2) === 1) {
					star.direction = 'leftTop';
				} else {
					star.direction = 'rightTop';
				}
			} else if (star.y < 2) {
				//触顶
				if (Math.floor(Math.random() * 2) === 1) {
					star.direction = 'rightBottom';
				} else {
					star.direction = 'leftBottom';
				}
			} else if (star.x < 2) {
				//左边
				if (Math.floor(Math.random() * 2) === 1) {
					star.direction = 'rightTop';
				} else {
					star.direction = 'rightBottom';
				}
			} else if (star.x - this.canvas.width > 0) {
				//右边
				if (Math.floor(Math.random() * 2) === 1) {
					star.direction = 'leftBottom';
				} else {
					star.direction = 'leftTop';
				}
			}
			if (star.direction === 'leftTop') {
				star.y -= star.radius / this.speed;
				star.x -= star.radius / this.speed;
			} else if (star.direction === 'rightBottom') {
				star.y += star.radius / this.speed;
				star.x += star.radius / this.speed;
			} else if (star.direction === 'leftBottom') {
				star.y += star.radius / this.speed;
				star.x -= star.radius / this.speed;
			} else if (star.direction === 'rightTop') {
				star.y -= star.radius / this.speed;
				star.x += star.radius / this.speed;
			}
			star.draw(this.context);
		},
		// ==============================================
		getCode() {
			getCodeImg().then(res => {
				this.captchaEnabled = res.captchaEnabled === undefined ? true : res.captchaEnabled;
				if (this.captchaEnabled) {
					this.codeUrl = 'data:image/gif;base64,' + res.img;
					this.loginForm.uuid = res.uuid;
				}
			});
		},
		getCookie() {
			const username = Cookies.get('username');
			const password = Cookies.get('password');
			const rememberMe = Cookies.get('rememberMe');
			this.loginForm = {
				username: username === undefined ? this.loginForm.username : username,
				password: password === undefined ? this.loginForm.password : decrypt(password),
				rememberMe: rememberMe === undefined ? false : Boolean(rememberMe)
			};
		},
		handleLogin() {
			this.$refs.loginForm.validate(valid => {
				if (valid) {
					this.loading = true;
					if (this.loginForm.rememberMe) {
						Cookies.set('username', this.loginForm.username, { expires: 30 });
						Cookies.set('password', encrypt(this.loginForm.password), { expires: 30 });
						Cookies.set('rememberMe', this.loginForm.rememberMe, { expires: 30 });
					} else {
						Cookies.remove('username');
						Cookies.remove('password');
						Cookies.remove('rememberMe');
					}
					this.$store
						.dispatch('Login', this.loginForm)
						.then(() => {
							this.$router.push({ path: this.redirect || '/' }).catch(() => {});
						})
						.catch(() => {
							this.loading = false;
							if (this.captchaEnabled) {
								this.getCode();
							}
						});
				}
			});
		}
	}
};
</script>

<style rel="stylesheet/scss" lang="scss">
.login {
	display: flex;
	justify-content: center;
	align-items: center;
	height: 100%;
	background-image: url('../assets/images/login-background.jpg');
	background-size: cover;
	#bgd {
		height: 100vh;
		width: 100vw;
		overflow: hidden;
	}
}
.title {
	margin: 0px auto 30px auto;
	text-align: center;
	color: #fff;
}

.login-form {
	border-radius: 6px;
	width: 400px;
	padding: 25px 25px 5px 25px;
	background: linear-gradient(230deg, rgba(53, 57, 74, 0) 0%, rgb(0, 0, 0) 100%);
	.el-input {
		height: 38px;
		input {
			background-color: transparent;
			color: #39f;
			height: 38px;
		}
	}
	.input-icon {
		height: 39px;
		width: 14px;
		margin-left: 2px;
	}
}
#loginBox {
	width: 420px;
	height: 390px;
	position: absolute;
	top: 0;
	left: 0;
	right: 0;
	bottom: 0;
	margin: auto;
	opacity: 1;
}
.login-tip {
	font-size: 13px;
	text-align: center;
	color: #bfbfbf;
}
.login-code {
	width: 33%;
	height: 38px;
	float: right;
	img {
		cursor: pointer;
		vertical-align: middle;
	}
}
.el-login-footer {
	height: 40px;
	line-height: 40px;
	position: fixed;
	bottom: 0;
	width: 100%;
	text-align: center;
	color: #fff;
	font-family: Arial;
	font-size: 12px;
	letter-spacing: 1px;
}
.login-code-img {
	height: 38px;
}
</style>
